Investigating experimental storage methodologies for the understudied intermediate recalcitrant seed of Northern Wild Rice (Zizania palustrisL.)

Abstract

The maintenance of plant genetic diversity is an essential target for conservation and breeding efforts. However, the ability to store seed varies between species with those that are more easily stored being overrepresented in seed banks. Northern Wild Rice (NWR; Zizania palustris) has intermediately recalcitrant seed which, along with its dormancy period, makes it more challenging to store long term. This study evaluated alternate storage treatments, including water changes, aeration, and the shift from submerged to moist seed, to extend the longevity of NWR seed in storage compared to current best management practices. Monthly water changes were the most effective storage treatment, maintaining greater than ~ 50% viability for over 28 months. There was a negative correlation found between aerated treatments with high dissolved oxygen and seed viability. Submerged to moist storage was only effective for ~16 months. Control treatments maintained relatively high viability (≥ 58%) through 21 months of storage. However, by 28 months, monthly water change seed had significantly higher viability (57.6%) compared to either the standard control (37.2%) or the bucket control (28.9%), suggesting that this treatment is more efficacious than standard storage conditions for maintaining seed viability of NWR.